Virtual network device

ABSTRACT

A virtual network device increases the effective number of local physical ports by converting each of the local physical ports into a plurality of virtual local physical ports, and the effective number of network physical ports by converting each of the network physical ports into a plurality of virtual network physical ports.

RELATED APPLICATION

The present application is a continuation-in-part of U.S. patentapplication Ser. No. 16/838,965 filed on Apr. 2, 2020.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present application relates to the field of computer networks and,in particular, to a virtual network device.

2. Description of the Related Art

A wide area network (WAN) is an interconnected web of network devicesthat typically interconnects local area networks or metropolitan areanetworks over a large geographical area, such as across the state oracross the country. WANs allow remotely located computers to communicatewith each other via the network devices.

Conventional network devices typically include one or more physicalnetwork ports that operate at a predetermined fixed data rate, such asfor example, 10/100/1000 Mbps (megabits per second), 10 Gbps (gigabitsper second), 40 Gbps, and 100 Gbps connection. As part of enablingcommunication between the computer systems over a network, conventionalnetwork devices negotiate the transfer speed of a network port and,during that process, the transfer speed of the network port is fixed.

One of the disadvantages of conventional network devices is that thereis often a requirement for more physical ports than are available, whichresults in reduced service or costly upgrades. As a result, there is aneed for an approach to accommodating the increasing need for ports.

SUMMARY OF THE INVENTION

The present invention provides a virtual network device with virtualports that effectively increase the number of available physical ports.The virtual network device includes a framing circuit that receives aplurality of input frames, examines the plurality of input frames todetermine a frame type for each input frame, and determines a virtualexit device associated with each input frame based on the frame type.The framing circuit also encapsulates the plurality of input frames toform a plurality of first encapsulated frames. Each virtual exit devicehas a receive virtual port. The plurality of first encapsulated frameshave a plurality of headers. The plurality of headers identifies aplurality of virtual exit devices that are associated with the pluralityof input frames. In addition, the virtual network device includes aplurality of transmit virtual ports that are coupled to the framingcircuit. The plurality of transmit virtual ports determine a pluralityof next hops in a virtual network for the plurality of firstencapsulated frames based on the virtual exit devices in the headers ofthe plurality of first encapsulated frames. The plurality of transmitvirtual ports additionally encapsulate the plurality of firstencapsulated frames to form a plurality of second encapsulated frames.Each second encapsulated frame has a header. The header of a secondencapsulated frame identifies a next hop of the second encapsulatedframe based on a next hop of a first encapsulated frame, and the receivevirtual port of the associated virtual exit device of an input frame.The transmit virtual ports include a first portion of a memory. Further,the virtual network device includes a transmit virtual switch coupled tothe plurality of transmit virtual ports. The transmit virtual switchselectively couples the transmit virtual ports to a network physicalport.

The present invention also includes a method of operating a virtualnetwork device. The method includes receiving a plurality of inputframes, examining the plurality of input frames to determine a frametype for each input frame, and determining a virtual exit deviceassociated with each input frame based on the frame type. Each virtualexit device has a receive virtual port. The method also includesencapsulating the plurality of input frames to form a plurality of firstencapsulated frames. The plurality of first encapsulated frames has aplurality of headers. The plurality of headers identifies a plurality ofvirtual exit devices associated with the plurality of input frames. Inaddition, the method includes determining a plurality of next hops in avirtual network for the plurality of first encapsulated frames based onthe virtual exit devices in the headers of the plurality of firstencapsulated frames. Further, the method includes encapsulating aplurality of first encapsulated frames in a plurality of transmitvirtual ports to form a plurality of second encapsulated frames. Eachsecond encapsulated frame has a header. The header of a secondencapsulated frame identifies a next hop of the second encapsulatedframe based on a next hop of a first encapsulated frame, and the receivevirtual port of the associated virtual exit device of an input frame.The transmit virtual ports include a first portion of a shared memory.The method additionally includes selectively coupling the transmitvirtual ports to a network physical port.

The present invention also provides a non-transitory computer-readablestorage medium having embedded therein program instructions, which whenexecuted by a processor causes the processor to execute a method ofoperating a virtual network device. The method includes receiving aplurality of input frames, examining the plurality of input frames todetermine a frame type for each input frame, and determining a virtualexit device associated with each input frame based on the frame type.Each virtual exit device has a receive virtual port. The method alsoincludes encapsulating the plurality of input frames to form a pluralityof first encapsulated frames. The plurality of first encapsulated frameshas a plurality of headers. The plurality of headers identifies aplurality of virtual exit devices associated with the plurality of inputframes. In addition, the method includes determining a plurality of nexthops in a virtual network for the plurality of first encapsulated framesbased on the virtual exit devices in the headers of the plurality offirst encapsulated frames. Further, the method includes encapsulating aplurality of first encapsulated frames in a plurality of transmitvirtual ports to form a plurality of second encapsulated frames. Eachsecond encapsulated frame has a header. The header of a secondencapsulated frame identifies a next hop of the second encapsulatedframe based on a next hop of a first encapsulated frame, and the receivevirtual port of the associated virtual exit device of an input frame.The method additionally includes selectively coupling the transmitvirtual ports to a network physical port.

A better understanding of the features and advantages of the presentinvention will be obtained by reference to the following detaileddescription and accompanying drawings which set forth an illustrativeembodiment in which the principals of the invention are utilized.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an example of a virtual networkdevice 100 in accordance with the present invention.

FIG. 2A is a block diagram illustrating an example of a transmit circuit200 in accordance with the present invention.

FIG. 2B is a block diagram illustrating an example of a transmit circuit250 in accordance with the present invention.

FIG. 3A is a flow chart illustrating an example of a method 300 ofoperating transmit circuit 200 in accordance with the present invention.

FIG. 3B is a flow chart illustrating an example of a method 350 ofoperating transmit circuit 200 in accordance with the present invention.

FIG. 4 is a block diagram illustrating an example of a transmit circuit400 in accordance with an alternate embodiment of the present invention.

FIG. 5 shows a block diagram that illustrates an example of a transmitcircuit 500 in accordance with an alternate embodiment of the presentinvention.

FIG. 6 is a block diagram illustrating an example of a receive circuit600 in accordance with the present invention.

FIG. 7 shows a flow chart illustrating an example of a method 700 ofoperating receive circuit 600 in accordance with the present invention.

FIG. 8 is a block diagram illustrating an example of a receive circuit800 in accordance with an alternate embodiment of the present invention.

FIG. 9 is a block diagram illustrating an example of a receive circuit900 in accordance with an alternate embodiment of the present invention.

A better understanding of the features and advantages of the presentinvention will be obtained by reference to the following detaileddescription and accompanying drawings which set forth an illustrativeembodiment in which the principals of the invention are utilized.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a block diagram that illustrates an example of a virtualnetwork device 100 in accordance with the present invention. Asdescribed in greater detail below, the effective number of localphysical ports in virtual network device 100 are increased by convertingone or more of the local physical ports into a plurality of virtuallocal physical ports, and the effective number of network physical portsare increased by converting one or more of the network physical portsinto a plurality of virtual network physical ports.

Virtual network device 100 is a component in a virtual network thatinterconnects a local router/switch with a remote router/switch. Thevirtual network includes a virtual network device 100, which functionsas a virtual entry device into the virtual network, that is coupled to alocal router/switch, and a virtual network device 100, which functionsas a virtual exit device from the virtual network, that is coupled to aremote router/switch.

As shown in FIG. 1, virtual network device 100 includes a transmitcircuit 110 that has a number of local physical ports 112 that eachreceive frames of data, such as set-top box (STB), personal computer(PC), and video frames of data, from a local network device, such as arouter/switch, and a number of network physical ports 114 that eachoutput frames of data to the virtual network.

As further shown in FIG. 1, virtual network device 100 also includes areceive circuit 120 that has a number of local physical ports 122 thateach output frames of data to a local network device, such as arouter/switch, and a number of network physical ports 124 that eachreceive frames of data from the virtual network. In one embodiment, oneor more of the local physical ports 112 and 122 can be shared betweenthe transmit and receive circuits 110 and 120, and one or more of thenetwork physical ports 114 and 124 can be shared between the transmitand receive circuits 110 and 120.

In addition, virtual network device 100 includes a shared memory 130that is coupled to both the transmit circuit 110 and the receive circuit120. Shared memory 130 includes a transmit queue that temporarily storesframes of data to be output to the virtual network, and a receive queuethat temporarily stores frames of data received from the virtualnetwork.

FIG. 2A shows a block diagram that illustrates an example of a transmitcircuit 200 in accordance with the present invention. As shown in FIG.2A, transmit circuit 200 includes a local physical port 210, a framingcircuit 212 that is coupled to local physical port 210, and a number oftransmit virtual ports vPORTa1-vPORTan that are coupled to framingcircuit 212.

Each transmit virtual port vPORTa, in turn, includes a transmit queueand a transmit frame formatting circuit. In addition, transmit circuit200 also includes a transmit virtual switch 214 that is coupled to eachof the transmit virtual ports vPORTa, and a network physical port 216that is coupled to transmit virtual switch 214.

FIG. 3A shows a flow chart that illustrates an example of a method 300of operating transmit circuit 200 in accordance with the presentinvention. As shown in FIG. 3A, method 300 begins at 310 with framingcircuit 212 receiving a series of input frames from local physical port210. Method 300 next moves to 312 to examine the series of input framesto determine a frame type (e.g., STB, PC, video) for each input frame,and then moves to 314 to determine a virtual exit device that isassociated with each input frame based on the frame type. Each virtualexit device, in turn, has a number of receive virtual ports.

Following this, method 300 moves to 316 where framing circuit 212encapsulates the series of input frames to form a number of firstencapsulated (FE) frames. The FE frames have headers that identify thevirtual exit devices that are associated with the series of inputframes.

After this, method 300 moves to 318 where the transmit virtual portsvPORTa1-vPORTan determine the next hops in a virtual network for the FEframes based on the virtual exit devices in the headers of the FEframes. Next, method 300 moves to 320 where the transmit virtual portsvPORTa1-vPORTan encapsulate the FE frames to form second encapsulated(SE) frames. Each SE frame has a header that identifies a next hop ofthe SE frame based on the next hop of a FE frame. The header alsoidentifies the receive virtual port of the associated virtual exitdevice of an input frame. In addition, the transmit virtual ports occupya first portion of a shared memory.

Following this, method 300 moves to 322 where transmit virtual switch214 cycles through the transmit virtual ports vPORTa1-vPORTansequentially forwarding a SE frame from each transmit virtual portvPORTa in a fixed repeating order to output a sequence of SE frames. Forexample, virtual switch 214 can output a sequence of SE frames where thefirst SE frame is from vPORT1, the second frame is from vPORT2, thethird frame is from vPORT3, and a fourth frame is again from vPORT1.

If a transmit virtual port vPORTa is empty or partially full, then noframe is generated. For example, if transmit virtual port vPORT2 isempty, then network physical port 216 outputs a frame sequence thatincludes frame 1, no frame, frame 3. Method 300 next moves to 324 wherenetwork physical port 216 transmits the sequence of SE frames onto thevirtual network.

FIG. 3B shows a flow chart that illustrates an example of a method 350of operating transmit circuit 200 in accordance with an alternateembodiment of the present invention. Method 350 is similar to method 300and, as a result, utilizes the same reference numerals to designate theelements that are common to both methods.

As shown in FIG. 3B, method 350 first diverges from method 300 at 352where virtual switch 214 determines whether a full signal has beenreceived from any of the transmit virtual ports vPORTa. The full signalindicates that the SE frame in a transmit virtual port vPORTa is readyto be transmitted. When virtual switch 214 detects a full signal from atransmit virtual port vPORTa, method 350 moves to 354 where virtualswitch 214 forwards the SE frame from the transmit virtual port vPORTathat output the full signal to network physical port 216.

For example, virtual switch 214 could sequentially receive a full signalfrom transmit virtual port vPORTa1, transmit virtual port vPORTa2, andtransmit virtual port vPORTa3. In this case, virtual switch 214 outputsa sequence of SE frames where the first SE frame is from transmitvirtual port vPORT1, the second frame is from transmit virtual portvPORT2, and the third frame is from transmit virtual port vPORT3.

Alternately, one of the sources (e.g., the STB, PC, video sources) canhave a data rate that is much faster than the data rates of the othersources (e.g., STB, PC, video sources) which, in turn, causes onetransmit virtual port vPORTa to output a full signal much morefrequently than the other transmit virtual ports vPORTa.

For example, if network physical port 216 transmits frames at a framerate of five frames per second, transmit virtual port vPORTa2 outputsframes at a rate that is 3× faster than each of the frame rates oftransmit virtual ports vPORTa1 and vPORTa3, transmit virtual portvPORTa2 signals full three times before the other ports, and transmitvirtual port vPORTa1 signals before vPORTa3 signals, then virtual switch214 forwards a sequence of frames that includes a first frame from thetransmit virtual port vPORT2, a second frame from transmit virtual portvPORT2, a third frame from transmit virtual port vPORT2, a fourth framefrom transmit virtual port vPORT1, and a fifth frame from transmitvirtual port vPORT3.

In addition to a first-in first-out approach where the order ofreceiving a full signal determines the order that a SE frame is outputfrom a transmit virtual port vPORTa by virtual switch 214, the transmitvirtual ports vPORTa-vPORTan can alternately include a priority schemethat allows frames to be forwarded from a transmit virtual port vPORTato a network physical port in any amount and in any order.

Referring back to FIG. 3B, after virtual switch 214 forwards the SEframe from the transmit virtual port vPORTa that output the full signalto network physical port 216, method 350 moves to 356 where networkphysical port 216 transmits the SE frame. In method 300, the frame to beoutput is predictable, whereas the frame to be output in method 350 isnot predictable, although a priority scheme provides a level ofpredictability.

Referring again to the FIG. 2A example, framing circuit 212 includes avirtual switch 220 and a framer 222 that is coupled to virtual switch220. Virtual switch 220 detects a type of input frame (e.g., STB, PC,video), determines a route for a frame to a virtual port vPORTa thatcorresponds with the type of frame from a static forwarding table, andoutputs the frame towards the virtual port vPORTa.

In the present example, virtual switch 220 receives the STB frametransmitted by a local source router/switch, and detects the receivedframe to be a STB frame from the source and/or destination MAC addressin the STB frame. Switch 220 then outputs the STB frame on a firstvirtual port line P1 routed towards virtual port vPORTa1, which waspre-selected to receive STB frames.

Similarly, virtual switch 220 receives the PC frame transmitted by thelocal source router/switch, and detects the received frame to be a PCframe from the source and/or destination MAC address in the PC frame.Switch 220 then outputs the PC frame on a second virtual port line P2routed towards virtual port vPORTa2, which was pre-selected to receivePC frames.

Virtual switch 220 also receives the video frame transmitted by thelocal router/switch, detects the received frame to be a video frame fromthe source and/or destination MAC address in the video frame, and thenoutputs the video frame on a third virtual port line P3 routed towardsvirtual port vPORTa3, which was pre-selected to receive video frames.

Framer 222 receives the STB frame on virtual port line P1, encapsulatesthe STB frame to form a first encapsulated (FE) STB frame, and thenforwards the FE STB frame to the transmit queue of virtual port vPORTa1.Similarly, framer 222 receives the PC frame on virtual port line P2,encapsulates the PC frame to form a first encapsulated (FE) PC frame,and then forwards the FE PC frame to the transmit queue of virtual portvPORTa2. Framer 222 also receives the video frame on virtual port lineP3, encapsulates the video frame to form a first encapsulated (FE) videoframe, and then forwards the FE video frame to the transmit queue ofvirtual port vPORTa3.

Framer 222 can utilize a conventional protocol, such as the providerbackbone bridge-traffic engineering (PBB-TE) protocol or the transportmultiprotocol label switching (T-MPLS) protocol, to generate theencapsulated frames. In addition, the FE STB frame, the FE PC frame, andthe FE video frame each has a header which has a number of fields thatinclude an identification of the virtual exit device.

For example, the header of a FE frame can include an exit address fieldfor the MAC address of the virtual exit device, an I-Tag field, or asimilar field. The header can also include other fields, such as the MACaddress of the virtual entry device. In the present example, the MACaddress of the virtual exit device is administratively provided to thevirtual entry device.

The frame formatting circuit in virtual port vPORTa1 of transmit circuit200 receives the FE STB frame, determines a next hop in the virtualnetwork for the FE STB frame from a static forwarding table based on theidentification of the virtual exit device, such as the MAC address ofthe virtual exit device, in the header of the FE STB frame, andencapsulates the FE STB frame to form a second encapsulated (SE) STBframe.

Similarly, the frame formatting circuit in virtual port vPORTa2 oftransmit circuit 200 receives the FE PC frame, determines a next hop inthe virtual network for the FE PC frame from the static forwarding tablebased on the identification of the virtual exit device, such as the MACaddress of the virtual exit device, in the header of the FE PC frame,and encapsulates the FE PC frame to form a second encapsulated (SE) PCframe.

In addition, the frame formatting circuit in virtual port vPORTa3 oftransmit circuit 200 receives the FE video frame, determines a next hopin the virtual network for the FE video frame from the static forwardingtable based on the identification of the virtual exit device, such asthe MAC address of the virtual exit device, in the header of the FEvideo frame, and encapsulates the FE video frame to form a secondencapsulated (SE) video frame.

The SE STB frame, the SE PC frame, and the SE video frame each includesa header with a next hop field that identifies the MAC address of thenext hop in the virtual network, a source field Src_vID that identifiesthe virtual port number of the virtual entry device, and a destinationfield Dst_vID that identifies a virtual port number of the virtual exitdevice that corresponds with the virtual port number of the virtualentry device. In the present example, the source field Src_vID for theSE STB frame is virtual port vPORTa1. Other fields, such as a last hopfield, can also be included.

Further, virtual switch 214 cycles through the virtual portsvPORTa1-vPORTan sequentially forwarding a second encapsulated (SE) framefrom each virtual port vPORTa to output a series of SE frames tophysical port 216. In the present example, switch 214 forwards a SE STBframe from virtual port vPORTa1 to physical port 216, followed byforwarding a SE PC frame from virtual port vPORTa2 to physical port 216,followed by forwarding a SE video frame from virtual port vPORTa3 tophysical port 216, followed by forwarding a SE STB frame from virtualport vPORTa1 to physical port 216, and continuing in the same manner,with physical port 216 outputting the frames. Although FIG. 2illustrates transmit circuit 200 as receiving and operating with inputfrom a single local router/switch, transmit circuit 200 can alternatelyreceive and operate with input from multiple router/switches.

FIG. 2B shows a block diagram that illustrates an example of a transmitcircuit 250 in accordance with the present invention. Transmit circuit250 is similar to transmit circuit 200 and, as a result, utilizes thesame reference numerals to designate the elements that are common toboth transmit circuit 200 and transmit circuit 250.

As shown in FIG. 2B, transmit circuit 250 differs from transmit circuit200 in that transmit circuit 250 includes a first network physical port216A and a second network physical port 216B, both of which are coupledto virtual switch 214. In addition, virtual switch 214 provides acontinuous connection between transmit virtual port vPORTa1 and networkphysical port 216A. Further, an additional transmit virtual port vPORTa4is shown.

Transmit circuit 250 operates substantially the same as transmit circuit200, except that one or more of the sources (e.g., STB, PC, or videosource) outputs frames of data at a frame rate that is greater than themaximum frame rate of the network physical ports 216A and 216B. Forexample, each of the network physical ports 216A and 216B can have amaximum frame rate of five frames per second.

In the FIG. 2B example, a set-top box outputs seven STB frames persecond, while a personal computer outputs two PC frames per second and avideo device outputs one video frame per second. (The numbers cited arefor illustration purposes only.) As shown in FIG. 2B, five of the sevenSTB frames are transmitted from network physical port 216A, while theremaining two STB frames, two PC frames, and one video frame aretransmitted from network physical port 216B in the manner illustrated bymethods 300 and 350. One the advantages of transmit circuit 250 is thattransmit circuit 250 can handle incoming frame rates that are greaterthan the maximum frame rate of the network physical ports.

FIG. 4 shows a block diagram that illustrates an example of a transmitcircuit 400 in accordance with an alternate embodiment of the presentinvention. Transmit circuit 400 is similar to transmit circuit 200 and,as a result, utilizes the same reference numerals to designate thestructures that are common to both circuits.

As shown in FIG. 4, transmit circuit 400 differs from transmit circuit200 in that framing circuit 212 of transmit circuit 400 utilizes aserial-to-serial framer 410 followed by a serial-to-parallel virtualswitch 412 that is coupled to the virtual ports vPORTa1-vPORTan in lieuof virtual switch 220 followed by framer 222.

In a further alternate embodiment, framer 410 and virtual switch 412 oftransmit circuit 400 can be physically separated, with framer 410 beingincorporated into a local router/switch.

FIG. 5 shows a block diagram that illustrates an example of a transmitcircuit 500 in accordance with the present invention. Transmit circuit500 is similar to transmit circuit 400 and, as a result, utilizes thesame reference numerals to designate the structures that are common toboth circuit 400 and circuit 500. As shown in the example illustrated inFIG. 5, a local framer router/switch 510 is utilized with transmitcircuit 500 in lieu of a local router/switch that receives and outputsSTB, PC, and video frames.

FIG. 6 shows a block diagram that illustrates an example of a receivecircuit 600 in accordance with the present invention. As shown in FIG.6, receive circuit 600 includes a network physical port 610 and areceive virtual switch 612 that is coupled to network physical port 610.Receive circuit 600 also includes a number of receive virtual portsvPORTb1-vPORTbn that are coupled to switch 612. Each receive virtualport vPORTb, in turn, includes a receive queue and a receive frameformatting circuit. Receive circuit 600 further includes a de-framingcircuit 614 that is coupled to each of the receive virtual ports vPORTb,and a local physical port 616 that is coupled to de-framing circuit 614.

FIG. 7 shows a flow chart that illustrates an example of a method 700 ofoperating receive circuit 600 in accordance with the present invention.As shown in FIG. 7, method 700 begins at 710 with network physical port610 receiving a series of third encapsulated (TE) frames from thevirtual network. The TE frames have headers that include next hopaddresses and receive virtual port identifiers.

Next, method 700 moves to 712 where network physical port 610 examinesthe TE frames to determine next hop addresses, and compares the next hopaddresses to a stored address. After this, method 700 moves to 714 wherenetwork physical port 610 forwards the TE frames with matching next hopaddresses as matching encapsulated (ME) frames. In addition, port 610drops the received TE frame when the identity of the next hop addressdoes not match the stored address.

After this, method 700 moves to 716 where receive virtual switch 612switchably passes the ME frames based on the receive virtual portidentifiers in the headers of the ME frames. Method 700 then moves to718 where the receive virtual ports vPORTb1-vPORTbn unpack theswitchably-passed ME frames to extract fourth encapsulated frames fromthe switchably-passed ME frames such that each receive virtual portvPORTb unpacks a ME frame to extract a fourth encapsulated frame. Thereceive virtual ports occupy a second portion of the shared memory.

Following this, method 700 moves to 720 where de-framing circuit 614unpacks the fourth encapsulated frames to extract the original STB, PC,and video input frames from the fourth encapsulated frames. The originalSTB, PC, and video input frames, which are from a remote router/switch,have a number of frame types. Further, each input frame has a headerthat identifies a destination router/switch. Method 700 then moves to722 where de-framing circuit 614 forwards the STB, PC, and video framesto local physical port 616, which outputs the original STB, PC, andvideo frames to a local router/switch.

In the present example, virtual switch 612 receives a ME STB frame fromnetwork physical port 610, and determines that the destination virtualport is virtual port vPORTb1 from the destination virtual port numberDst_vID in the header of the ME STB frame. In addition, switch 612determines a route to virtual port vPORTb1 from the static forwardingtable, and then outputs the ME STB frame on a first virtual port linerouted towards virtual port vPORTb1.

Similarly, virtual switch 612 receives a ME PC frame from networkphysical port 610, and determines that the destination virtual port isvirtual port vPORTb2 from the destination virtual port number Dst_vID inthe header of the ME PC frame. Further, switch 612 determines a route tovirtual port vPORTb2 from the static forwarding table, and then outputsthe ME PC frame on a second virtual port line routed towards virtualport vPORTb2.

In addition, virtual switch 612 receives a ME video frame from networkphysical port 610, and determines that the destination virtual port isvirtual port vPORTb3 from the destination virtual port number Dst_vID inthe header of the ME video frame. Switch 612 determines a route tovirtual port vPORTb3 from the static forwarding table, and then outputsthe ME video frame on a third virtual port line routed towards virtualport vPORTb3.

The virtual ports vPORTb1-vPORTbn receive the ME frames, and unpack theME frames to extract the fourth encapsulated frames, such as a fourthencapsulated STB frame, a fourth encapsulated PC frame, and a fourthencapsulated video frame, from the ME frames. In the FIG. 6 example, thereceive queue of a first virtual port vPORTb1 receives a ME STB frame,while the frame formatting circuit of virtual port vPORTb1 unpacks theME STB frame to extract the fourth encapsulated STB frame, which has aheader that includes the identity of the virtual exit device.

Similarly, the receive queue of a second virtual port vPORTb2 receives aME PC frame, while the frame formatting circuit of virtual port vPORTb2unpacks the ME PC frame to extract the fourth encapsulated PC frame,which has a header that includes the identity of the virtual exitdevice. In addition, the receive queue of a third virtual port vPORTb3receives a ME video frame, while the frame formatting circuit of virtualport vPORTb3 unpacks the ME video frame to extract the fourthencapsulated video frame, which has a header that includes the identityof the virtual exit device.

De-framing circuit 614 receives the plurality of fourth encapsulatedframes, and extracts the original STB, PC, and video input frames fromthe fourth encapsulated frames. The input frames have a number of frametypes, e.g., STB, PC, video. Each input frame has a header that includesthe identity of a destination router/switch. For each received fourthencapsulated frame, de-framing circuit 614 unpacks a fourth encapsulatedframe to extract an input frame, determines an identity of a destinationrouter/switch from the header of the input frame, and outputs the inputframe to local physical port 616, which outputs the input frame to thedestination router/switch.

As shown in FIG. 6, de-framing circuit 614 includes a de-framer 620 anda virtual switch 622 that is coupled to de-framer 620. In operation,de-framer 620 receives the fourth encapsulated frames from the pluralityof receive virtual ports vPORTb1-vPORTbn, and unpacks the fourthencapsulated frames to extract the original input frames, e.g., the STBframe, the PC frame, and the video frame, and forwards the STB frame,the PC frame, and the video frame to virtual switch 622.

In the FIG. 6 example, de-framer 620 receives the fourth encapsulatedSTB frame from receive virtual port vPORTb1, unpacks the fourthencapsulated frame to extract the STB frame, and forwards the STB frameto virtual switch 622. Similarly, de-framer 620 receives the fourthencapsulated PC frame from receive virtual port vPORTb2, unpacks thefourth encapsulated frame to extract the PC frame, and forwards the PCframe to virtual switch 622. In addition, de-framer 620 receives thefourth encapsulated video frame from receive virtual port vPORTb3,unpacks the fourth encapsulated frame to extract the video frame, andforwards the video frame to virtual switch 622. De-framer 620 canutilize the same or different protocol as framer 222.

Virtual switch 622 cycles through the outputs of de-framer 620sequentially receiving and forwarding output frames to local physicalport 616. In the present example, virtual switch 622 receives the STBframe from de-framer 620, detects the MAC address of a destinationrouter/switch, and outputs the STB frame to local physical port 616.Similarly, virtual switch 622 receives the PC frame from de-framer 620,detects the MAC address of a destination router/switch, and outputs thePC frame to local physical port 616. In addition, virtual switch 622receives the video frame from de-framer 620, detects the MAC address ofa destination router/switch, and outputs the video frame to localphysical port 616. Local physical port 616, in turn, outputs the framesto a local router/switch.

The FIG. 6 example illustrates de-framing circuit 614 with aparallel-to-parallel de-framer 620 followed by a parallel-to-serialvirtual switch 622. De-framing circuit 614 can be alternately realizedwith other circuit arrangements. For example, de-framing circuit 614 canbe implemented with a serial-to-parallel virtual switch that is coupledto the virtual ports vPORTb1-vPORTbn followed by a serial-to-serialframer.

FIG. 8 shows a block diagram that illustrates an example of a receivecircuit 800 in accordance with an alternate embodiment of the presentinvention. Receive circuit 800 is similar to receive circuit 600 and, asa result, utilizes the same reference numerals to designate thestructures that are common to both circuits.

As shown in FIG. 8, receive circuit 800 differs from receive circuit 600in that framing circuit 614 of receive circuit 800 includes aparallel-to-serial virtual switch 810 that is coupled to the virtualports vPORTb1-vPORTbn, followed by a serial-to-serial de-framer 812. Theimplementations of framing circuit 212 and de-framing circuit 614 can beinterchanged. For example, virtual network device 100 can utilizeframing circuit 212 implemented with virtual switch 220 and framer 222,while de-framing circuit 614 can be implemented with virtual switch 810and de-framer 812.

In a further alternate embodiment, virtual switch 810 and de-framer 812can be physically separated, with de-framer 812 being incorporated intoa local router/switch.

FIG. 9 shows a block diagram that illustrates an example of a receivecircuit 900 in accordance with the present invention. Receive circuit900 is similar to receive circuit 800 and, as a result, utilizes thesame reference numerals to designate the structures that are common toboth circuit 800 and circuit 900. As shown in the example illustrated inFIG. 9, a local de-framer router/switch 910 is utilized in receivecircuit 900 in lieu of a local router switch.

One of the advantages of the present invention is that the presentinvention combines multiple streams of STB, PC, and video frames into asingle virtual frame stream via a number of virtual ports which, inturn, effectively increases the number of available physical ports.

Reference has now been made in detail to the various embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings. While described in conjunction with the variousembodiments, it will be understood that these various embodiments arenot intended to limit the present disclosure. On the contrary, thepresent disclosure is intended to cover alternatives, modifications andequivalents, which may be included within the scope of the presentdisclosure as construed according to the claims.

Furthermore, in the preceding detailed description of variousembodiments of the present disclosure, numerous specific details are setforth in order to provide a thorough understanding of the presentdisclosure. However, it will be recognized by one of ordinary skill inthe art that the present disclosure may be practiced without thesespecific details or with equivalents thereof. In other instances,well-known methods, procedures, components, and circuits have not beendescribed in detail so as not to unnecessarily obscure aspects ofvarious embodiments of the present disclosure.

It is noted that although a method may be depicted herein as a sequenceof numbered operations for clarity, the numbering does not necessarilydictate the order of the operations. It should be understood that someof the operations may be skipped, performed in parallel, or performedwithout the requirement of maintaining a strict order of sequence.

The drawings showing various embodiments in accordance with the presentdisclosure are semi-diagrammatic and not to scale and, particularly,some of the dimensions are for the clarity of presentation and are shownexaggerated in the drawing Figures. Similarly, although the views in thedrawings for the ease of description generally show similarorientations, this depiction in the figures is arbitrary for the mostpart. Generally, the various embodiments in accordance with the presentdisclosure can be operated in any orientation.

Some portions of the detailed descriptions are presented in terms ofprocedures, logic blocks, processing, and other symbolic representationsof operations on data bits within a computer memory. These descriptionsand representations are used by those skilled in the data processingarts to effectively convey the substance of their work to others skilledin the art.

In the present disclosure, a procedure, logic block, process, or thelike, is conceived to be a self-consistent sequence of operations orinstructions leading to a desired result. The operations are thoseutilizing physical manipulations of physical quantities. Usually,although not necessarily, these quantities take the form of electricalor magnetic signals capable of being stored, transferred, combined,compared, and otherwise manipulated in a computing system. It has provenconvenient at times, principally for reasons of common usage, to referto these signals as transactions, bits, values, elements, symbols,characters, samples, pixels, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the followingdiscussions, it is appreciated that throughout the present disclosure,discussions utilizing terms such as “generating,” “determining,”“assigning,” “aggregating,” “utilizing,” “virtualizing,” “processing,”“accessing,” “executing,” “storing,” or the like, refer to the actionand processes of a computer system, or similar electronic computingdevice or processor.

The computing system, or similar electronic computing device orprocessor manipulates and transforms data represented as physical(electronic) quantities within the computer system memories, registers,other such information storage, and/or other computer readable mediainto other data similarly represented as physical quantities within thecomputer system memories or registers or other such information storage,transmission or display devices.

The technical solutions in the embodiments of the present applicationhave been clearly and completely described in the prior sections withreference to the drawings of the embodiments of the present application.It should be noted that the terms “first,” “second,” and the like in thedescription and claims of the present invention and in the abovedrawings are used to distinguish similar objects and are not necessarilyused to describe a specific sequence or order. It should be understoodthat these numbers may be interchanged where appropriate so that theembodiments of the present invention described herein can be implementedin orders other than those illustrated or described herein.

The functions described in the method of the present embodiment, ifimplemented in the form of a software functional unit and sold or usedas a standalone product, can be stored in a computing device readablestorage medium. Based on such understanding, a portion of theembodiments of the present application that contributes to the prior artor a portion of the technical solution may be embodied in the form of asoftware product stored in a storage medium, including a plurality ofinstructions for causing a computing device (which may be a personalcomputer, a server, a mobile computing device, or a network device, andso on) to perform all or part of the steps of the methods described invarious embodiments of the present application. The foregoing storagemedium includes: a USB drive, a portable hard disk, a read-only memory(ROM), a random-access memory (RAM), a magnetic disk, an optical disk,and the like, which can store program code.

The various embodiments in the specification of the present applicationare described in a progressive manner, and each embodiment focuses onits difference from other embodiments, and the same or similar partsbetween the various embodiments may be referred to another case. Thedescribed embodiments are only a part of the embodiments, rather thanall of the embodiments of the present application. All other embodimentsobtained by a person of ordinary skill in the art based on theembodiments of the present application without departing from theinventive skills are within the scope of the present application.

The above description of the disclosed embodiments enables a personskilled in the art to make or use the present application. Variousmodifications to these embodiments are obvious to a person skilled inthe art, and the general principles defined herein may be implemented inother embodiments without departing from the spirit or scope of thepresent application. Therefore, the present application is not limitedto the embodiments shown herein, but the broadest scope consistent withthe principles and novel features disclosed herein.

What is claimed is:
 1. A virtual network device, comprising: a framingcircuit to receive a plurality of input frames, examine the plurality ofinput frames to determine a frame type for each input frame, determine avirtual exit device associated with each input frame based on the frametype, and encapsulate the plurality of input frames to form a pluralityof first encapsulated frames, each virtual exit device having a receivevirtual port, the plurality of first encapsulated frames having aplurality of headers, the plurality of headers identifying a pluralityof virtual exit devices associated with the plurality of input frames; aplurality of transmit virtual ports coupled to the framing circuit, theplurality of transmit virtual ports to determine a plurality of nexthops in a virtual network for the plurality of first encapsulated framesbased on the virtual exit devices in the headers of the plurality offirst encapsulated frames, and encapsulate the plurality of firstencapsulated frames to form a plurality of second encapsulated frames,each second encapsulated frame having a header, the header of a secondencapsulated frame identifying a next hop of the second encapsulatedframe based on a next hop of a first encapsulated frame, and the receivevirtual port of the associated virtual exit device of an input frame;and a transmit virtual switch coupled to the plurality of transmitvirtual ports, the transmit virtual switch to selectively couple thetransmit virtual ports to a network physical port.
 2. The virtualnetwork device of claim 1 wherein the transmit virtual switch cyclesthrough the plurality of transmit virtual ports sequentially forwardinga second encapsulated frame from each transmit virtual port in a fixedrepeating order to output a series of second encapsulated frames.
 3. Thevirtual network device of claim 1 wherein the transmit virtual switchreceives a full signal from a transmit virtual port, and forwards aframe from the transmit virtual port that output the full signal to thenetwork physical port.
 4. The virtual network device of claim 1 whereinthe framing circuit includes: a virtual switch that determines a routefor a frame to a transmit virtual port based on the frame type, andoutputs the frame towards the transmit virtual port; and a framercoupled to the virtual switch, the framer to encapsulate the inputframes.
 5. The virtual network device of claim 4 wherein the framerexecutes a protocol from a group of protocols that include a providerbackbone bridge-traffic engineering (PBB-TE) protocol and a transfermultiprotocol listing switch (T-MPLS) protocol.
 6. The virtual networkdevice of claim 1 wherein the transmit virtual ports include a firstportion of a shared memory.
 7. The virtual network device of claim 6 andfurther comprising: a receive physical port that receives a plurality ofthird encapsulated frames, examines the plurality of third encapsulatedframes to determine a plurality of frame destinations, compares theplurality of frame destinations to a stored destination, and forwardsthe third encapsulated frames with matching destinations as matchingencapsulated frames, the plurality of third encapsulated frames andmatching encapsulated frames having a plurality of headers, theplurality of headers having a plurality of receive virtual portidentifiers; a receive virtual switch coupled to the receive physicalport, the receive virtual switch to switchably pass the matchingencapsulated frames based on the receive virtual port identifiers in theheaders of the matching encapsulated frames; a plurality of receivevirtual ports coupled to the receive virtual switch, the plurality ofreceive virtual ports to unpack the switchably-passed matchingencapsulated frames to extract a plurality of fourth encapsulated framesfrom the plurality of matching encapsulated frames such that eachreceive virtual port unpacks a matching encapsulated frame to extract afourth encapsulated frame, the receive virtual ports including a secondportion of the shared memory; and a de-framing circuit coupled to theplurality of receive virtual ports, the de-framing circuit to unpack theplurality of fourth encapsulated frames to extract a plurality of outputframes from the plurality of fourth encapsulated frames, the pluralityof output frames having a plurality of frame types, each output framehaving a header that identifies a destination router/switch.
 8. Thevirtual network device of claim 7 wherein the de-framing circuitincludes a de-framer that receives the fourth encapsulated frames fromthe plurality of receive virtual ports, and unpacks the fourthencapsulated frames to extract the input frames.
 9. The virtual networkdevice of claim 8 wherein the framing circuit outputs the input framesto a local router/switch.
 10. A method of operating a virtual networkdevice, the method comprising: receiving a plurality of input frames;examining the plurality of input frames to determine a frame type foreach input frame; determining a virtual exit device associated with eachinput frame based on the frame type, each virtual exit device having areceive virtual port; encapsulating the plurality of input frames toform a plurality of first encapsulated frames, the plurality of firstencapsulated frames having a plurality of headers, the plurality ofheaders identifying a plurality of virtual exit devices associated withthe plurality of input frames; determining a plurality of next hops in avirtual network for the plurality of first encapsulated frames based onthe virtual exit devices in the headers of the plurality of firstencapsulated frames; encapsulating a plurality of first encapsulatedframes in a plurality of transmit virtual ports to form a plurality ofsecond encapsulated frames, each second encapsulated frame having aheader, the header of a second encapsulated frame identifying a next hopof the second encapsulated frame based on a next hop of a firstencapsulated frame, and the receive virtual port of the associatedvirtual exit device of an input frame; and selectively coupling thetransmit virtual ports to a network physical port.
 11. The method ofclaim 10, further comprising cycling through the plurality of transmitvirtual ports sequentially forwarding a second encapsulated frame fromeach transmit virtual port in a fixed repeating order to output a seriesof second encapsulated frames.
 12. The method of claim 10, furthercomprising receiving a full signal from a transmit virtual port, andforwarding a frame from the transmit virtual port that output the fullsignal to the network physical port.
 13. The method of claim 10, furthercomprising determining a route for a frame to a transmit virtual portbased on the frame type, and outputting the frame towards the transmitvirtual port.
 14. The method of claim 10 wherein the plurality of inputframes is encapsulated with a protocol from a group of protocols thatinclude a provider backbone bridge-traffic engineering (PBB-TE) protocoland a transfer multiprotocol listing switch (T-MPLS) protocol.
 15. Themethod of claim 10 wherein the transmit virtual ports include a firstportion of a shared memory.
 16. The method of claim 15, furthercomprising: receiving a plurality of third encapsulated frames;examining the plurality of third encapsulated frames to determine aplurality of frame destinations; comparing the plurality of framedestinations to a stored destination; forwarding the third encapsulatedframes with matching destinations as matching encapsulated frames, theplurality of third encapsulated frames and matching encapsulated frameshaving a plurality of headers, the plurality of headers having aplurality of receive virtual port identifiers; switchably passing thematching encapsulated frames based on the receive virtual portidentifiers in the headers of the matching encapsulated frames;unpacking the switchably-passed matching encapsulated frames in aplurality of receive virtual ports to extract a plurality of fourthencapsulated frames from the plurality of matching encapsulated framessuch that each receive virtual port unpacks a matching encapsulatedframe to extract a fourth encapsulated frame, the receive virtual portsincluding a second portion of the shared memory; and unpacking theplurality of fourth encapsulated frames to extract a plurality of outputframes from the plurality of fourth encapsulated frames, the pluralityof output frames having a plurality of frame types, each output framehaving a header that identifies a destination router/switch.
 17. Anon-transitory computer-readable storage medium having embedded thereinprogram instructions, which when executed by a processor causes theprocessor to execute a method of operating a virtual network device, themethod comprising: receiving a plurality of input frames; examining theplurality of input frames to determine a frame type for each inputframe; determining a virtual exit device associated with each inputframe based on the frame type, each virtual exit device having a receivevirtual port; encapsulating the plurality of input frames to form aplurality of first encapsulated frames, the plurality of firstencapsulated frames having a plurality of headers, the plurality ofheaders identifying a plurality of virtual exit devices associated withthe plurality of input frames; determining a plurality of next hops in avirtual network for the plurality of first encapsulated frames based onthe virtual exit devices in the headers of the plurality of firstencapsulated frames; encapsulating a plurality of first encapsulatedframes in a plurality of transmit virtual ports to form a plurality ofsecond encapsulated frames, each second encapsulated frame having aheader, the header of a second encapsulated frame identifying a next hopof the second encapsulated frame based on a next hop of a firstencapsulated frame, and the receive virtual port of the associatedvirtual exit device of an input frame; and selectively coupling thetransmit virtual ports to a network physical port.
 18. The medium ofclaim 17, wherein the method further comprises cycling through theplurality of transmit virtual ports sequentially forwarding a secondencapsulated frame from each transmit virtual port in a fixed repeatingorder to output a series of second encapsulated frames.
 19. The mediumof claim 17, wherein the method further comprises receiving a fullsignal from a transmit virtual port, and forwarding a frame from thetransmit virtual port that output the full signal to the networkphysical port.
 20. The medium of claim 19, wherein the method furthercomprises: receiving a plurality of third encapsulated frames; examiningthe plurality of third encapsulated frames to determine a plurality offrame destinations; comparing the plurality of frame destinations to astored destination; forwarding each third encapsulated frame with amatching destination as a matching encapsulated frame to forward aplurality of matching encapsulated frames, the plurality of thirdencapsulated frames and matching encapsulated frames having a pluralityof headers, the plurality of headers having a plurality of receivevirtual port identifiers; switchably passing the matching encapsulatedframes based on the receive virtual port identifiers in the headers ofthe matching encapsulated frames; unpacking the switchably-passedmatching encapsulated frames in a plurality of receive virtual ports toextract a plurality of fourth encapsulated frames from the plurality ofmatching encapsulated frames such that each receive virtual port unpacksa matching encapsulated frame to extract a fourth encapsulated frame,the receive virtual ports including a second portion of the sharedmemory; and unpacking the plurality of fourth encapsulated frames toextract a plurality of output frames from the plurality of fourthencapsulated frames, the plurality of output frames having a pluralityof frame types, each output frame having a header that identifies adestination router/switch.